What causes "Database name is null or empty." in apache/seatunnel?

Always specify an explicit database name in the table path, e.g. schema.table instead of just table.

apache/seatunnel · error · CatalogException

Database name is null or empty.

Error message

Database name is null or empty.

What it means

HudiCatalog.databaseExists treats a null or empty database name as a programming/config error rather than a false result, throwing CatalogException. The catalog identifies databases as subdirectories under the table parent path, so a valid non-empty name is required to check existence.

Source

Thrown at seatunnel-connectors-v2/connector-hudi/src/main/java/org/apache/seatunnel/connectors/seatunnel/hudi/catalog/HudiCatalog.java:126

        } catch (Exception e) {
            log.info("Hudi catalog close error.", e);
        }
    }

    @Override
    public String name() {
        return catalogName;
    }

    @Override
    public String getDefaultDatabase() throws CatalogException {
        return "default";
    }

    @Override
    public boolean databaseExists(String databaseName) throws CatalogException {
        if (StringUtils.isEmpty(databaseName)) {
            throw new CatalogException("Database name is null or empty.");
        }
        return listDatabases().contains(databaseName);
    }

    @Override
    public List<String> listDatabases() throws CatalogException {
        try {
            FileStatus[] fileStatuses = fs.listStatus(tableParentDfsPath);
            return Arrays.stream(fileStatuses)
                    .filter(FileStatus::isDirectory)
                    .map(fileStatus -> fileStatus.getPath().getName())
                    .collect(Collectors.toList());
        } catch (IOException e) {
            throw new CatalogException("Listing database exception.", e);
        }
    }

    @Override

View on GitHub (pinned to cf67b549a7)

Solutions

Always specify an explicit database name in the table path, e.g. schema.table instead of just table.
Set the catalog's default database if you intend to rely on it, ensuring it is non-empty.
Fix caller code that constructs TablePath to fill in the database field.
Validate the database name is non-blank before invoking catalog APIs.

Example fix

// before
TablePath.of("", "my_table")
// after
TablePath.of("my_db", "my_table")

Defensive patterns

Strategy: validation

Validate before calling

if (databaseName == null || databaseName.trim().isEmpty()) {
    throw new IllegalArgumentException("database name must be a non-empty string");
}

Try / catch

try {
    boolean exists = catalog.databaseExists(db);
} catch (CatalogException e) {
    throw new IllegalArgumentException("Provide a non-empty database name: " + e.getMessage(), e);
}

Prevention

Always build TablePath with both database and table (schema.table).
Check for empty database fields when parsing user-supplied table identifiers.
Rely on the catalog default database only after confirming it is configured.

When it happens

Trigger: Calling databaseExists(null) or databaseExists("") directly, or indirectly via listTables/createDatabase/dropDatabase with an empty database portion of the TablePath, or via open() with a blank default database.

Common situations: TablePath built without a database component (only table name); config option for database left empty; user code passing empty string assuming defaults are applied.

Understand the failure class

Background: "must not be empty", "cannot be empty" — required-field validation errors across open-source libraries — this error's family across 41 libraries.

Related errors

AI-assisted analysis of apache/seatunnel@cf67b549a7 (2026-09-10). Data as JSON: /api/errors/90cb897ba6504be5. Report an issue: GitHub.